Hold down bar for rail car hatch covers

Abstract

A hold down bar for securing adjacent hatch covers of a hopper car and for further sealing the gap that exists between those covers includes a latch arm formed from spring steel in the configuration of an inverted U so as to have a generally straight midportion and legs which are directed downwardly and outwardly from the midportion. In addition, the bar has a resilient shoe which fits against and is attached to the midportion of the latch arm, but is shorter than the space between the two legs so that it can be adjusted back and forth in that space and thus positioned with considerable precision with regard to underlying hatch covers. The shoe in turn carries a gasket that seats against the adjacent hatch covers along a gap between them to effect a water tight seal with those latch covers. Being formed from spring steel, the latch arm will deflect in the presence of heavy impacts, such as derived from the latch covers being dropped on them, but will not take on a permanent deformation. One leg of the latch arm is rolled into a knuckle which receives a bushing sized to fit into the space between two tabs on a hinge bracket located on the roof of the rail car, and this bushing is secured within the knuckle by washers which fit over and are attached to it so that the knuckle is captured between the washers. Thus by varying bushings a single latch arm and likewise the bar of which it forms a part can accommodate various hinge brackets.

What is claimed is: 
     
       1. In combination with a car roof having a hatch in it and at least two covers which are capable of fitting over the hatch with their ends adjacent such that a slight gap exists between the adjacent ends, an improved hold down bar for securing the covers to the roof at their adjacent ends and for further closing the gap between such covers so that the gap will not admit contaminants, said hold down bar comprising: a latch arm which at one end is pivotally connected to the roof on one side of the hatch and at its other end is adapted to be fastened to the roof on the other side of the hatch, the latch arm being formed from a resilient material and being substantially flat in cross-section intermediate its ends so that it is capable of flexing easily intermediate its ends; a shoe attached to the latch arm and being formed from a resilient material which enables it to flex with the arm; and gasket attached to the shoe and being configured to generally conform to the upper surface of the hatch covers at the adjacent ends of those hatch covers, the latch arm being configured such that it flexes easily against the natural resiliency of the material from which it is formed and undergoes a perceptible change in shape as its other end is brought down toward and fastened to the roof with the shoe and gasket interposed between the arm and the covers. 
     
     
       2. The combination according to claim 1 wherein the shoe is detachable from the latch arm. 
     
     
       3. The combination according to claim 1 wherein the shoe is attached to the latch arm with screws which permit the shoe and the gasket carried by it to be detached from the latch arms. 
     
     
       4. The combination according to claim 1 wherein the latch arm is of an inverted U-shape, it having a midportion that extends generally along the gap and downwardly directed legs, one of the legs being pivotally connected to the roof and the other being adapted to be fastened to the roof; and wherein the shoe is attached to the latch arm along the midportion and between the legs of the latch arm. 
     
     
       5. The combination according to claim 4 wherein the shoe is shorter than the distance between the legs of the latch arm, and is attached to the midportion such that its position between the legs may be adjusted. 
     
     
       6. The combination according to claim 4 wherein the midportion of the latch arm has a camber which tends to cause its center to be presented somewhat lower than its ends when the latch arm is unrestrained. 
     
     
       7. The combination according to claim 4 wherein the one leg of the latch arm which is pivotally connected to the roof has a knuckle at its end, and further comprising a bushing extending through the knuckle and washers attached to the bushing on each side of the knuckle such that the knuckle is captured between the washers. 
     
     
       8. The combination according to claim 7 wherein the roof along one side of the hatch is provided with a pair of tabs, and wherein the bushing in the knuckle of the latch arm fits between the tabs and a pin extends through the tabs and the bushing to pivotally connect the latch arm to the roof. 
     
     
       9. A hold down bar for securing a hatch cover over a hatch in the roof of a rail car; said hold down bar comprising: a latch arm in the configuration of an inverted U so as to have a midportion and downwardly directed legs at the ends of the midportion, one of the legs having a hinge knuckle formed on it and the other leg being configured to engage a latching device on the roof of the car, the latch arm being formed from spring steel and otherwise being of a cross-sectional configuration which enables it to easily flex without undergoing a permanent deformation; a shoe attached to the midportion of the latch arm and being located between the legs of the midportion, the shoe being formed from a resilient material so that it will flex with the latch arm; and an elastomeric gasket attached to the shoe and being configured to seat against a hatch cover, the midportion of the latch arm being configured such that when the legs of the latch arm are unrestrained, the midportion of the latch arm possesses a slight curvature as does the shoe and the gasket, so that the gasket assumes a somewhat convex shape intermediate its ends on its downwardly presented surface. 
     
     
       10. A hold down bar according to claim 9 wherein the length of the shoe is less than the distance between the two legs of the latch arm; and wherein the shoe is attached to the midportion of the latch arm such that it may be adjusted longitudinally of the latch arm in the space between the legs of the latch arm. 
     
     
       11. A hold down bar according to claim 9 wherein the shoe on one of its sides terminates above the gasket and on its other side is provided with a skirt which projects downwardly below the gasket. 
     
     
       12. A hold down bar according to claim 9 and further comprising a bushing extending through the knuckle on the one leg of the latch arm and projecting beyond both ends of the knuckle and washers attached to the bushing at each end of the knuckle so that the knuckle is captured between the washers. 
     
     
       13. In combination with a car roof having a hatch in it and at least two covers which are capable of fitting over the hatch with their ends adjacent such that a slight gap exists between the adjacent ends, an improved hold down bar for securing the covers to the roof at their adjacent ends and for further closing the gap between such covers so that the gap will not admit contaminants, said hold down bar comprising: a latch arm of inverted U-shape, it having a midportion that extends generally along the gap and downwardly directed legs, the latch arm at one of the legs being pivotally connected to the roof on one side of the hatch and at the other leg being adapted to be fastened to the roof on the other side of the hatch, the latch arm being formed from a resilient material that is capable of flexing; a shoe attached to the latch arm along the midportion of the arm between the legs of the arm, the shoe being shorter than the distance between the legs of the arm and the attachment being such that the position of the shoe between the legs may be adjusted, the shoe being formed from a resilient material which enables it to flex with the latch arm; and a gasket attached to the shoe and being configured to generally conform to the upper surface of the hatch covers at the adjacent ends of those hatch covers. 
     
     
       14. The combination according to claim 13 wherein the midportion of the latch arm contains at least one slot, the longitudinal axis of which is parallel to the longitudinal axis of the midportion; and wherein a screw passes through the slot and into the shoe and when tightened down secures the shoe in the desired position on the latch arm. 
     
     
       15. The combination according to claim 14 wherein the shoe has a nut embedded in it and the screw is a cap screw which passes through the slot and threads into the nut in the shoe. 
     
     
       16. The combination according to claim 14 wherein the shoe has an upwardly opening groove and the midportion of the latch arm is received in that groove. 
     
     
       17. The combination according to claim 16 wherein the midportion of the latch arm has a camber which presents its center somewhat lower than its ends when the latch arm is unrestrained. 
     
     
       18. The combination according to claim 16 wherein the shoe also has a downwardly opening groove and the gasket fits into the groove and projects downwardly out of it. 
     
     
       19. A hold down bar for securing a hatch cover over a hatch in the roof of a rail car; said hold down bar comprising: a latch arm in the configuration of an inverted U so as to have a midportion, downwardly directed legs at the ends of the midportion, one of the legs having a hinge knuckle formed on it and the other leg being configured to engage a latching device on the roof of the car, the latch arm being formed from a resilient material so that it may flex without undergoing a permanent deformation; a shoe attached to the midportion of the latch arm and being located between the legs of the midportion, the length of the shoe being less than the distance between the two legs of the latch arm and the shoe being attached to the midportion of the latch arm such that it may be adjusted longitudinally of the latch arm in the space between the legs of the latch arm, the shoe being formed from a resilient material so that it will flex with the latch arm; and an elastomeric gasket attached to the shoe and being configured to seat against a hatch cover. 
     
     
       20. A hold down bar according to claim 19 wherein the shoe contains an upwardly opening groove in which the midportion of the latch arm is received. 
     
     
       21. A hold down bar according to claim 19 wherein the midportion of the latch arm contains at least one slot, the major axis of which is generally parallel to the longitudinal axis of the midportion, and wherein a screw extends through the slot and into the shoe to attach the shoe to the latch arm. 
     
     
       22. A hold down bar according to claim 21 wherein the shoe also has a downwardly opening groove in which the gasket is received. 
     
     
       23. In combination with a car roof having a hatch in it and at least two covers which are capable of fitting over the hatch with their ends adjacent such that a slight gap exists between the adjacent ends, the covers being hinged with respect to the roof along one side of the hatch, so as to expose the hatch when the covers are raised over center and then allowed to drop downwardly, an improved hold down bar for securing the covers to the roof at their adjacent ends and for further closing the gap between such covers so that the gap will not admit contaminants, said hold down bar comprising: a latch arm having a raised midportion that is long enough to extend across the covers at the gap and legs at each end of the midportion, the latch arm at one leg being pivotally connected to the roof on the side of the hatch at which the covers are hinged and at its other end being adapted to be fastened to the roof on the other side of the hatch, the latch arm being formed from spring steel and within at least its midportion being of a cross-section that enables it to easily flex, a shoe attached to the latch arm along the midportion thereof and being formed from a resilient material which enables it to flex with the arm; and a gasket attached to the shoe and being configured to generally conform to the upper surface of the hatch covers at the adjacent ends of those hatch covers, whereby the hold down bar can be swung upwardly about the pivotal connection of its latch arm away from the hatch and cover to an over center position and thence downwardly to an open position in which the gasket is presented upwardly, the resiliency of the latch arm, shoe and gasket being such that when a cover is raised over center and allowed to drop downwardly without restraint onto the hold down bar, the latch arm, shoe and gasket will all flex without undergoing a permanent deformation. 
     
     
       24. The combination according to claim 23 wherein the latch arm possesses a flat cross-section in its legs as well as through its midportion; and wherein the midportion of the latch arm possesses a slight camber when unrestrained, but the camber is substantially eliminated when the hold down bar extends over the covers and the other end of its latch arm is fastened to the roof.